Quick-acting clamp



United States Patent O 2,855,964 QUICK-ACTING CLAMP Bernard H. Zelazny, San Francisco, Calif., assgnor of one-half to Sidney Le Fiel/l, San Francisco, Calif.

Application June 11, 1957, Serial No. 664,987

1 Claim` (Cl. 144305) This invention relates to improvements in quick-acting clamps and has particular reference to a C-type clamp wherein material of different thicknesses may be readily clamped one to the other.

A further object is to produce a clamp which may be quickly adjusted to accommodate for the various thicknesses and thereafter pressure may be applied to the two jaws of the clamp to cause an intimate binding action.

A further object is to produce a clamp which iseconomical to manufacture, one which is easy to use and one wherein the two clamping members will remain in alignment during the clamping operation.

Other objects -and advantages will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numbers are employed to designate like parts throughout the same,

Fig. 1 is a side elevation of my clamp; and

Fig. 2 is a cross sectional view taken on the line 2 2 of Fig. 1.

The ordinary C-clamp consists of a C-shaped frame, one end of the frame serving to support one of the jaws of the clamp, while the other end of the frame serves to support a pivoted member upon which a moveable jaw is carried, and by rotating this pivoted member, pressure can be exerted between the two jaws.

Applicant has devised a means whereby the clamp may be quickly adjusted to the approximate distance between the two jaws and thereafter to exert a very heavy pressure between the two jaws in a manner which takes practically no time, in counter-distinction to the threaded-clamping means so often employed in the ordinary C-type clamp.

Also, this arrangement permits of the quick release of the material and the replacing of the clamp upon similar thicknesses without further adjusting.

In the accompanying drawings, wherein for the purpose of illustration is shown a preferred embodiment of my invention, the numeral 5 designates a frame member having a nose 6 which forms one of the jaws of the clamp.

To the opposite end of the frame member is pivoted as at 7 a rocker arm 8, in which is slidably mounted a pressure bar 9 carrying a moveable jaw 11. The bar 9 has a at surface 12 upon which teeth 13 are formed.

These teeth are in turn engaged by a spring pressed pawl 14.

ICS

2 A handle 16 is carried by the lower end of the bar 9. Pivoted to the frame 5 as at 17 is a toggle link 18 which is in turn pivoted as at 19 to the toggle lever 21 pivoted as at 22 to a threaded member 24, which extends through the bifurcated end 26 of the rocker arm 8 and is engaged by a nut 27.

The result of this construction is that when material is placed between the jaws as shown at A, the first act is to push the bar 9 toward the jaw 6 until the jaw 11 contacts the material being Worked upon. The nut 27 is now adjusted so that the jaw 11 just contacts the material, and thereafter the toggle lever 21 is moved from the dotted line position to its full line position, thus moving the bifurcated end of the rocker arm downwardly to cause pivotal action and compression between the jaws 6 and 11.

It is to be here noted that the bar 9 passes through a tapered bore 28 in the rocker arm and consequently, as this pivotal action takes place, there is no movement between the two jaws, as the bar will rock upon the end of the detent 14, thus permitting the change in arc in the rocker arm without transmitting this arcuate movement to the jaw 11.

It will thus be seen that by a simple manipulation of the toggle lever,lthe clamp can be forcibly closed and quickly unlocked with a minimum amount of effort, and that the clamp may be quickly adjusted by rotating the bar 9 a quarter turn so as to release the teeth 13 from the pawl whenever desired.

It will thus be seen that I have devised a clamp which will accomplish all of the objectives above set forth. It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same and that various changes relative to the material, size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claim.

Having thus described my invention, I claim:

A clamp comprising a substantially Cshaped frame having a fixed jaw at one end thereof, a rocker arm pivoted intermediate its ends to the other end of said frame, an adjustable toggle linkage connecting one end of said rocker arm and said frame, said rocker arm having its free end provided with a tapered bore in axial alignment with said fixed jaw, the large end of said bore opening toward the xed jaw, a pressure bar loosely slidable in said bore, said bar having teeth formed thereon, a spring-pressed pawl carried by said rocker arm and engaging the teeth of said bar, whereby said bar may slide and rock in said bore, and a movable jaw formed on said bar to engage work positioned between said jaws.

References Cited in the tile of this patent UNITED STATES PATENTS 1,445,344 Moltrup Feb. 13, 1923 1,749,491 Kokay Mar. 4, 1930 1,886,874 Draim Nov. 8, 1932 2,466,937 Downs Apr. 12, 1949 pllrwusuvlulnp.. Fb 16 

